Fuel composition having a fuel, water, a high molecular weight emulsifier, and a surfactant including natural fats, non-ionic and ionic surfactants, co-surfactants, fatty acids and their amine salts, or combinations thereof

ABSTRACT

The invention provides an emulsified water in oil composition comprising: A) a fuel; B) a water; C) a high molecular weight emulsifier; D) a surfactant having a molecular weight of about less than or equal to about 950 g/mol wherein the surfactant comprises: i) natural fats; ii) non-ionic and ionic surfactants; iii) co-surfactant; iv) fatty acids and their amine salts; or v) combinations thereof; and E) optionally ammonium nitrate.

This application is a continuation of U.S. Ser. No. 10/319,668 filedDec. 13, 2002 and claims the benefit of said prior application.

FIELD OF INVENTION

The invention relates to a novel low energy process to produce a waterin oil emulsion, in particular water blended fuels with good emulsionstability. More particularly, the invention relates to the use of a lowmolecular weight surfactant to make a water in oil emulsion by a lowenergy, low shear process.

BACKGROUND OF THE INVENTION

Internal combustion engines, especially diesel engines, using water fuelblends results in the combustion chamber producing lower nitrogen oxides(NO_(x)), hydrocarbons and particulate matter emissions. NO_(x)emissions have become an important environmental issue because itcontributes to smog and air pollution. Governmental regulations andenvironmental concerns have driven the need to reduce NO_(x) emissionsfrom engines. In particular, the U.S. Clean Air Act will require about90% to 95% reduction of the current level of internal combustion enginesemissions by the year 2007. Similar regulations are expected in Europeand other parts of the industrialized world.

Diesel fueled engines produce NO, due to the relatively high flametemperatures reached during combustion. The reduction of NO_(x)production conventionally includes the use of catalytic converters,using “clean” fuels, recirculation of exhaust and engine timing changes.These methods are typically expensive or complicated to be readilycommercially available.

Water is inert toward combustion, but lowers the peak combustiontemperature resulting in reduced particulates and NO_(x) formation. Whenwater is added to the fuel it forms an emulsion and these emulsions aregenerally unstable. Stable water in fuel emulsions of a small particlesize are difficult to reach and maintain.

The use of emulsified fuels to reduce emissions have been disclosed inother patents and patent applications of Applicant, such as U.S. Pat.Nos. 6,280,485, 6,383,237, 6,368,367, 6,368,366 and 6,280,485 and U.S.Ser. No. 09/761,482 all incorporated herein by reference and assigned tothe assignee of the present application. Emulsified fuels have been madeby high energy intensive processes. It would be advantageous to developa low energy process to make stable water in fuel emulsions.

The present invention has discovered the use of certain low molecularweight surfactants that lower interfacial tension at the water oilinterface resulting in a low energy process to make a water in oilemulsion fuels.

The term “NO_(x)” is used herein to refer to any of the nitrogen oxides,NO, NO₂, N₂O, or mixtures of two or more thereof. The terms“water-in-oil” emulsion, “water emulsion”, “emulsions”, “water blendedfuel”, “emulsified water fuel” and other variations are interchangeable.

SUMMARY OF THE INVENTION

The invention relates to an emulsified water in oil compositioncomprising:

A. a fuel in the range of about 50% to about 99% by weight of thecomposition;

B. a water in the range of about 1% to about 50% by weight of thecomposition;

C. an emulsifier in the range of about 1% to about 50% by weight of thecomposition;

D. a low molecular weight surfactant in the range of about 0.001% toabout 15% by weight of the composition wherein the surfactant comprises:

-   -   i) natural fats;    -   ii) non-ionic and ionic surfactants;    -   iii) co-surfactants;    -   iv) fatty acids and their amine salts; or    -   v) combinations thereof; and

E. optionally ammonium nitrate.

The surfactant lowers the interfacial tension of the water in oilinterface during emulsion and formation and is a low molecular weightsurfactant that is less than or equal to 950 g/mol.

Further, the invention relates to a low energy process for making awater in oil emulsion comprising emulsifying a fuel, a water, anemulsifier, and a low-molecular weight surfactant. The water in oilemulsion is produced utilizing a low energy processing technology usinglow shear rates and does not need to employ high shear rates.

The invention further relates to a low energy process to produce anemulsified water in oil composition from a concentrate comprisingemulsifying a portion of a fuel, a portion to substantially all of awater depending on whether it is an emulsified concentrate or anadditive concentrate, substantially all of an emulsifier, substantiallyall of a low molecular weight surfactant to form a concentrate emulsion;and then diluting the concentrated emulsion with the remaining portionof fuel and water at the time of use.

The water in oil emulsion provides good emulsion stability. The water inoil composition is useful as a fuel for stationary and/or combustionengines and/or open flame burning apparatus.

DETAILED DESCRIPTION

The invention discloses a stable emulsified water in oil compositionmade by a low energy process by low shearing the emulsion. Theemulsified water in oil composition employs a low molecular weightsurfactant so that a low shear rate mixing condition can be used to makethe emulsion.

Surfactant

The surfactant is a small surfactant, having a molecular weight (Mw) ofabout less than or equal to about 950 g/mol, in another embodiment about900 g/mol to about 30 g/mol, in another embodiment about 400 g/mol toabout 90 g/mol, and in another embodiment about 350 g/mol to about 150g/mol. Further the low molecular weight surfactant has properties tolower the interfacial tension at the water/oil interface during emulsionformation. The low molecular weight surfactant further orients itself tothe water/oil interface quickly by populating the water oil interface.The use of the low molecular weight surfactant results in a low energyprocess to make the water in oil emulsion, in particular an emulsifiedwater fuel.

The surfactant includes but is not limited to a) natural fats; b)non-ionics surfactants; c) co-surfactants; d) fatty acids and theiramine salts; and e) combinations thereof. The surfactant is in the rangeof about 0.001% to about 15%, in another embodiment about 0.01% to about10%, in another embodiment about 0.05% to about 5%, and in anotherembodiment about 0.1% to about 3% by weight of the water in oilcomposition. The surfactants can be used alone or in combination. In oneembodiment the preferred surfactant is a natural fat surfactant.

The natural fat surfactants include but are not limited totriglycerides, hydrolyzed triglycerides, oxidized products oftriglycerides, vegetable oils, refined vegetable oils, used vegetableoils and the like. The preferred natural fat surfactant is a refinedused vegetable oil. The natural fats can be used alone or incombination.

The non ionic and ionic surfactants include but are not limited to alkylethoxylates, ethoxylated alkylphenols, alkyl glucosides, ethoxylatedalcohols, ethoxylated amines, amides derived from fatty acids and/oralcohols, ethers or fatty alcohols, esters of fatty acids and the like.In addition the non-ionic and ionic surfactants have a hydrophiliclipohilic balance (HLB) in the range of about 2 to about 40, in oneembodiment, about 2 to about 10, in one embodiment about 10 to about 15and in another embodiment about 4 to about 8. Examples of thesenon-ionic and ionic surfactants are disclosed in McCutcheon'sEmulsifiers and Detergents, 1993, North American & InternationalEdition. Some examples include but are not limited to alkanolamides,alkylarylsulfonates, amine oxides, poly(oxyalkylene) compounds,including block copolymers comprising alkylene oxide repeat units (e.g.PLURONIC® s), carboxylated alcohol ethoxylates, ethoxylated alcohols,ethoxylated alkyl phenols, ethoxylated amines and amides, ethoxylatedfatty acids, ethoxylated fatty esters and oils, fatty esters, glycerolesters, glycol esters, imidazoline derivatives, lecithin andderivatives, lignin and derivatives, monoglycerides, diglycerides andderivatives, phosphate esters and derivatives, propoxylated andethoxylated fatty acids or alcohols or alkyl phenols, sorbitanderivatives, sucrose esters and derivatives, sulfates or alcohols orethoxylated alcohols, sulfonates of dodecyl and tridecyl benzenes orcondensed naphthalenes or petroleum and the like. Preferably the nonionic surfactants are Neodol 25-3, C12-C14 alcohol with two ethoxylatesand Ethomeen C12. The non ionic and ionic surfactants may be used aloneor in combination.

Additionally, the ethoxylated alcohols include but are not limited tooleyl alcohol with 5 ethoxylates, Tomadol 91-8 (purchased from TomahChemical) and the like. The ethoxylated alcohol contains about 5 toabout 24, preferably about 8 to about 20 and more preferably about 5 toabout 12 carbon atoms with about 3 to about 30 preferably about 5 toabout 25 and more preferably about 5 to about 10 ethylene oxide groups.Preferably the ethoxylated alcohol is oleyl alcohol with 5 ethoxylates.The ethoxylated alcohols may be used alone or in combination.

Another example of non-ionic and ionic surfactants include but are notlimited to IGEPAL CO-630, (nonylphenoxypoly(ethyleneoxy) ethanol;nonoxynol-8), IGEPAL CO-430, IGEPAL CO 530, available fromRhone-Poulenc, Cranbury, N.J., USA; TERGITOL® NP-9(a-(4-nonylphenyl)-hydroxypoly(oxy-1,2-ethanediyl), available from UnionCarbide Corporation, Danbury, Conn., USA); and alcohol ethoxylatesavailable from Tomah Products, Inc. under the name “Tomadol”™ alcoholethoxylates and the like.

In another embodiment the non-ionic and ionic surfactants include butare not limited to sorbitan esters of fatty acids, sorbitan monooleate(SMO); sorbitan monoisostearate (SMIS); glycerol esters like glycerolmonooleate (GMO); glycerol dioleate; and mono-unsaturated acids such asoleic and elaidic acid; poly-unsaturated acids such as linoleic andlinolenic acid; 1,6-dilauryl diglycerol; monoleyl diglycerol; mono cetylether of glycerol; mono oleyl glycerol; diethylene glycol mono-stearate;and the like. In one embodiment the preferred non-ionic surfactants areglycerol monooleate, sorbitan monooleate and combinations thereof.

In another embodiment the non-ionic and ionic surfactants include butare not limited to esters of the fatty acids include but are not limitedto glyceryl mono-oleate, glyceryl monostearate, glycerylmonoricinolaeate, pentaerythritol monolaurate, pentaerythritol mono anddioleate, pentaerythritol monocaprylate, mono, di, and triethyleneglycol mono-oleate, propylene glycol monoricinoleate; monoethyleneglycol mono-oleate, triethylene glycol monostearate, sorbitolmonolaurate, mannitol mono-oleate, mannitol dioleate, sorbitol,dioleate, sorbitan dioleate, sorbitan mono and dilaurate, mannitan monoand distearate, mannitan mono and dioleate, sorbitan mono anddipalmitate, sorbitan sesquioleate, mannitan monolaurate, and the like.

Partial esters obtained from polyhydric alcohols are useful as thesurfactant include but are not limited to the cyclic ether-alcoholesters which have been modified by being further reaction with analkylene oxide or a polyalkyene oxide. For example, a sorbitanmono-oleate may be further modified by treatment with ethylene oxide toform the hydroxyl ether or sorbitan mono-oleate. Other modified estersof this type may be the polyoxyalklene sorbitan monostearate,polyoxyalkylene sorbitan mono-oleate, polyoxyalkylene sorbitanmonolaurate, polyoxyalkylene sorbiitan di and tri-oleate, oleic ester ofpolyoxyalkylene mannitol, and the like. In another embodiment thenon-ionic surfactants include but are not limited to the etherificationof the cyclic ether-alcohols of fatty acids containing 12 or more carbonatoms and may be derived from natural fats and oils or pure fatty acidsor their mixtures may be used. The free fatty acids may be exemplifiedby capric, palmitic, oleic, stearic acid or the like. In addition to thefatty acids other acids may be used and may be exemplified bynaphthenic, sulfonic, salicylic acids and the like.

In another embodiment the non-ionic and ionic surfactants include butare not limited to fatty acid alkanol amides such as available fromWitco Corporation under the name SCHERCOMID™, SCHERCOMID™SO-A andOleamide DEA, lauric acid, myristic acid, coconut acid, coconut oil,oleic acid, tall oil fatty acid, linoleic acid, soybean oil, apricotkernel oil, wheat germ oil, monocarboxylic fatty acids, triglycerides,and mixtures thereof.

The co-surfactant has sufficient polar groups to render theco-surfactant partially soluble in both phases. The co-surfactantsinclude but are no limited to alcohols, amines, amides, esters, ketones,ethers and mixtures thereof. The co-surfactant has at least 1 to about24, in another embodiment about 1 to about 10, in another embodimentabout 1 to about 8 carbon atoms. The co-surfactants may be used alone orin combination.

The alcohol co-surfactant has about 1 to about 6, in another embodimentabout 1 to about 4 and in another embodiment 1 to 3 hydroxy groups inthe molecule. Such alcohols may be aliphatic, saturated or unsaturated,and straight chain or branched or cyclic derivatives thereof. Saturated,aliphatic, straight chain alcohols are preferred. The alcoholsurfactants include but are not limited to propylene glycol, ethyleneglycol, isopropanol, 2 ethyl hexanol, stearyl alcohol, oleyl alcohol,methanol, ethanol and the like. The preferred alcohol surfactant ispropylene glycol. The alcohols may be used alone or in combinations.

The fatty acids and their amine salts include but are not limited toN,N-diethy ethanolamine salts of oleic acid, tall oil fatty acids,stearic acid, palmitic acid, lauric acid and the like. The preferablefatty acid and their amine salt is oleic acid-diethyl ethanol aminesalt. The fatty acids and their amine salts can be used alone or incombination.

The water in oil emulsion is comprised of a continuous fuel-phase, adiscontinuous water or aqueous phase, an emulsifying amount ofemulsifier and a low molecular weight surfactant so that the processdoes not require high speed shear to emulsify the fuel and water.

In the practice of the present invention the water in oil emulsion ismade by a batch, semi-batch or a continuous process. A concentrate maybe made and used. The process is capable of monitoring and adjusting theflow rates of the fuel, emulsifier, surfactant, additives and/or waterto form a stable emulsion with the desired water droplet size. The waterphase of the emulsified fuel is comprised of droplets having a meandiameter of about 1.0 microns or less, in another embodiment about 0.8microns or less, in another embodiment about 0.5 microns or less, inanother embodiment about 0.15 microns or more, in another embodimentabout 1.0 micron to about 0.5 microns, and in another embodiment about1.0 micron to about 0.2 microns.

The emulsified fuel may be prepared by the steps of mixing the fuel, theemulsifier, the low molecular weight surfactant, and other oil solubleadditive using low shear techniques to form the fuel additive mixture.Then the fuel additive mixture is mixed with water and optionally anydesired water soluble additives to form the desired emulsified waterblended fuel.

In a batch process the water, the emulsifier, the surfactant, the fueland optional additives are added to a tank, in the desired amounts. Themixture is emulsified using an emulsification device in the vessel, oralternatively the mixture flows from the vessel via a circular line tothe emulsification device which is external to the vessel, for about 1to about 20 tank turnovers. The temperature in the range of aboutambient temperature to about 212° F., and in another embodiment in therange of about 40° F. to about 150° F., and at a pressure in the rangeof about atmospheric pressure to about 10 atmospheres, in anotherembodiment about atmospheric pressure to about 80 psi, in anotherembodiment in the range of about 15 psi to about 30 psi.

The continuous process described herein depicts another embodiment ofthe invention. The feeds of the fuel, emulsifier, surfactant, water andoptional additives are introduced as discrete feeds or in thealternative combinations of the discreet feeds. The processing streamsare introduced in or as close to the inlet of the emulsification deviceas possible. It is preferable that the emulsifier is added to the fuelas a fuel emulsifier stream prior to the discreet feeds combiningtogether. The continuous process generally occurs under ambientconditions. The continuous process is generally done at atmosphericpressure to about 500 psi, in another embodiment in the range of aboutatmospheric pressure to about 120 psi, and in another embodiment in therange of about atmospheric pressure to about 50 psi. The continuousprocess generally occurs at ambient temperature. In one embodiment thetemperature is in the range of about ambient temperature to about 212°F., and in another embodiment in the range of about 40° F. to about 150°F.

Alternatively, a concentrate is formed and all or substantially all thewater, and water soluble additive and a portion of the fuel and all orsubstantially all the emulsifier and low molecular weight surfactant isemulsified under low shear conditions to form a concentrate fuel. Theemulsified fuel, when used, is then blended under normal mixingconditions with the remaining portion remaining portion of the fuel sothat high speed emulsification conditions are not necessary.

The process may be in the form of a containerized equipment unit thatoperates automatically. The process can be programmed and monitoredlocally at the site of its installation, or it can be programmed andmonitored from a location remote from the site of its installation. Thefully formulated water fuel blend is optionally dispensed to end usersat the installation site, or in another embodiment end users can blendthe concentrated emulsion with the final portion of fuel. This providesa way to make the water in fuel emulsions available to end users in widedistribution networks.

The emulsification may occur at high shear conditions that are greaterthan 50,000 s⁻¹. However, the composition is emulsified at low shearprocess conditions. The emulsification provides for the desired particlesize and a uniform dispersion of water in the fuel and occurs at a shearrate in the range of less than or equal to 50,000 sir, and in anotherembodiment about 50,000 s⁻¹ to about 20,000 s⁻¹, and in anotherembodiment of about 20,000 s⁻¹ to about 1,000 s⁻¹, and in anotherembodiment less than 1,000 s⁻¹ to about 1 s⁻¹, and in another embodimentless than 100 s⁻¹ to about less than 1 s⁻¹ and in another embodimentless than 10 s⁻¹ to about less than 1 s⁻¹ shearing. If more than oneemulsification step is used, the shear rates of the emulsification stepscan be the same, similar or different, depending on the emulsifier andlow molecular weight surfactant used.

The emulsification occurs by any low shear method used in the industryincluding but not limited to mixing, mechanical mixer agitation, staticmixers, centrifugal pumps, positive displacement pumps, orifice plates,and the like. Examples of the devices include but are not limited to anAquashear, pipeline static mixers, rotor/stator mixers and the like. TheAquashear is a low-pressure hydraulic shear device. The Aquashear mixersare available from Flow Process Technologies Inc.

The emulsification is able to occur at a low shear rate and does notrequire a high shear rate. By using a low shear rate, low energy processto make a stable and good emulsified water in oil blend/fuel one usesless complex or simpler technology, equipment, devices and is more costand/or time efficient.

EXAMPLE 1

About 0.3 parts by weight of glycerol monooleate and about 2.3 parts byweight of a concentrate mixture containing about 23% wt 2300 MW PIBsuccinic acid/diethyl ethanolamine salt plus about 31% wt oleicacid/diethyl ethanol amine salt plus about 9.7% of about a 50% ammoniumnitrate solution and about 4.7% propylene glycol is mixed into about77.0 parts by weight of diesel fuel. This organic mixture is then co-fedwith about 20 parts by weight water through an 8.0 mm diameter SulzerSMX static mixer unit consisting of about 48 mixing elements at a totalvolumetric flow rate of about 470 millilitres per minute. The finalwhite emulsion was placed in storage bottles. After standing for onemonth at room temperature, about 99% of the material was still anemulsion. No banding or water was observed and only about 1% of thediesel fuel had separated. Particle size, oil separation, andsedimentation were found to be comparable to emulsifiers made using highshear mixing. The particle size of the emulsion was found to have a meanvolume diameter of less than about 1 micron. The storage bottles werestored at room temperature and observed at various time intervals. Itwas observed that the emulsion exhibited stability behavior equivalentto emulsions made using high shear conditions, i.e. about 3 part byvolume (pbv) of banded material at the bottom of the storage bottleafter 7 days and about 7 pbv after 28 days. In addition no free waterwas observed.

Fuel

The fuel comprises hydrocarbonaceous petroleum distillate fuel,non-hydrocarbonaceous materials that include but are not limited towater, oils, liquid fuels derived from vegetable sources, liquid fuelsderived from minerals and mixtures thereof. Suitable fuels include, butare not limited to, gasoline, diesel, kerosene, naphtha, aliphatics andparaffin. The fuel comprises non-hydrocarbonaceous materials include butis not limited to alcohols such as methanol, ethanol and the like,ethers such as diethyl ether, methyl ethyl ether and the like,organo-nitro compounds and the like; fuels derived from vegetable ormineral sources such as corn, alfalfa, shale, coal and the like. Thefuel also includes but is not limited to gas to liquid fuels. The fuelalso includes but is not limited to mixtures of one or morehydrocarbonaceous fuels and one or more non-hydrocarbonaceous materials.Examples of such mixtures are combinations of gasoline and ethanol andof diesel fuel and ether and the like.

In one embodiment, the fuel is any gasoline. Including, but not limitedto a chlorine-free gasoline or a low-chlorine gasoline, or a low sulfurgasoline or sulfur-free gasoline and the like.

In one embodiment, the fuel is any diesel fuel. The diesel fuelsinclude, but are not limited to, those that contain alcohols and esters,has a sulfur content of up to about 0.05% by weight or sulfur-free, is achlorine-free or low-chlorine diesel fuel and the like.

The fuel is present in the emulsified fuel at a concentration of about50% to about 95% by weight, and in one embodiment about 60% to about 95%by weight, and in one embodiment about 65% to about 85% by weight, andin one embodiment about 80% to about 90% by weight of the emulsifiedfuel.

Water

The water used in the emulsified fuel may be taken from any source. Thewater includes but is not limited to tap, deionized, demineralized,purified, for example, using reverse osmosis or distillation, and thelike. The water includes water mixtures that further includes but arenot limited to antifreeze components such as alcohols and glycols,ammonium salts such as ammonium nitrate, ammonium maleate, ammoniumacetate and the like, and combinations thereof; and other water solubleadditives.

The water is present in the emulsified fuel at a concentration of about1% to about 50% by weight, in one embodiment about 5% to about 40% beingweight, in one embodiment about 5% to about 25% by weight, and in oneembodiment about 10% to about 20% by weight of the emulsified fuel.

In another embodiment the water is present in the emulsified fuel at aconcentration of less than 1% by weight, in another embodiment less than0.5% by weight, in another embodiment less than 0.1% by weight, and inanother embodiment in the range of about 0.1% to about 1% by weight ofthe emulsified fuel. An emulsified water in oil composition can be madewith water at these low levels with the fuel, the emulsifier, thesurfactant and optionally ammonium nitrate and in another embodimentwithout the surfactant and with the fuel, the emulsifier and optionallythe ammonium nitrate.

Emulsifier

The emulsifier includes but is not limited to

(i) at least one fuel-soluble product made by reacting at least onehydrocarbyl-substituted carboxylic acid acylating agent with ammonia oran amine including but not limited to alkanol amine, hydroxy amine, andthe like, the hydrocarbyl substituent of said acylating agent havingabout 50 to about 500 carbon atoms;

(ii) a second acylating agent having at least one hydrocarbylsubstituents of up to about 40 carbon atoms, and reacting that saidacylating agent with ammonia or an amine;

(iii) at least one of an ionic or a nonionic compound having ahydrophilic-lipophilic balance (HLB) of about 1 to about 40;

(iv) mixture of (ii) or (iii) with (i) or a mixture of (i), (ii), and(iii);

(v) a water-soluble compound selected from the group consisting of aminesalts, ammonium salts, azide compounds, nitrate esters, nitramine,nitrocompounds, alkali metal salts, alkaline earth metal salts, incombination with (i), (ii), (iii), (v), (vii) or combinations thereof;

(vi) the reaction product of polyacidic polymer with at least one fuelsoluble product made by reacting at least one hydrocarbyl-substitutedcarboxylic acid acylating agent with ammonia, an amine, a polyamine, analkanol amine or hydroxy amines;

(vii) an amino alkylphenol which is made by reacting an alkylphenol, analdehyde and an amine resulting in an amino alkylphenol;

(viii) a nitrogen free emulsifier; or

(ix) the combination of (i) through-(viii) or combinations thereof.

The emulsifier has at least one high molecular weight component. Theemulsifier has a high molecular weight component relative to thesurfactant which has a low molecular weight.

The fuel-soluble product (i) of the emulsifier may be at least onefuel-soluble product made by reacting at least onehydrocarbyl-substituted carboxylic acid acylating agent with ammonia oran amine including but not limited to alkanol amines, hydroxy amines,and the like, the hydrocarbyl substituent of said acylating agent havingabout 50 to about 500 carbon atoms, and is described in greater detailin U.S. Ser. No. 09/761,482, An Emulsifier For An Aqueous HydrocarbonFuel, incorporated by reference herein.

The hydrocarbyl-substituted carboxylic acid acylating agents may becarboxylic acids or reactive equivalents of such acids. The reactiveequivalents may be acid halides, anhydrides, or esters, includingpartial esters and the like. The hydrocarbyl substituents for thesecarboxylic acid acylating agents may contain from about 50 to about 500carbon atoms, and in one embodiment about 50 to about 300 carbon atoms,and in one embodiment about 60 to about 200 carbon atoms. In oneembodiment, the hydrocarbyl substituents of these acylating agents havenumber average molecular weights of about 700 to about 3000, and in oneembodiment about 900 to about 2300.

In another embodiment, the fuel soluble product (i) of the presentinvention comprises an emulsifying amount of at least one of afuel-soluble hydrocarbyl-substituted carboxylic acylating agent and areaction product of said acylating agent with at least one of ammonia,an amine, an alcohol, a reactive metal, a reactive metal compound or amixture of two or more thereof, wherein the hydrocarbyl substituentcomprises a group derived from at least one polyolefin, said polyolefinhaving {overscore (M)}_(w)/{overscore (M)}_(n) greater than about 5.

The hydrocarbyl substituted acylating agents have a hydrocarbyl groupsubstituent that is derived from a polyolefin, with polydispersity andother features as described below. Generally, it has a number averagemolecular weight of at least 600, 700, or 800, to 5000 or more, often upto 3000, 2500, 1600, 1300, or 1200. Typically, less than 5% by weight ofthe polyolefin molecules have {overscore (M)}_(n) less than about 250,more often the polyolefin has {overscore (M)}_(n) of at least about 800.The polyolefin preferably contains at least about 30% terminalvinylidene groups, more often at least about 60% and more preferably atleast about 75% or about 85% terminal vinylidene groups. The polyolefinhas polydispersity, {overscore (M)}_(w)/{overscore (M)}_(n), greaterthan about 5, more often from about 6 to about 20. The hydrocarbyl groupis typically derived from a polyolefin or a polymerizable derivativethereof, including homopolymers and interpolymers of olefin monomershaving 2 to 30, to 6, or to 4 carbon atoms, and mixtures thereof. In apreferred embodiment the polyolefin is polyisobutenyl.

Suitable olefin polymer hydrocarbyl groups, having suitablepolydispersity, can be prepared by heteropolyacid catalyzedpolymerization of olefins under conventional conditions. Preferredheteroplyacids include a phosphotungstic acid, a phosphomolybidc acid, asilicotungstic acid, a silicomolybdic acid and the like.

The hydrocarbyl-substituted carboxylic acid acylating agents may be madeby reacting one or more alpha-beta olefinically unsaturated carboxylicacid reagents containing 2 to about 20 carbon atoms, exclusive of thecarboxyl groups, with one or more olefin polymers as described morefully hereinafter. This reaction may occur under the conditions to addthe alpha-beta olefinically unsaturated carboxylic acid reagents via afree radical addition process.

In one embodiment, the hydrocarbyl-substituted carboxylic acid acylatingagent is a polyisobutene-substituted succinic anhydride, thepolyisobutene substituent having a number average molecular weight ofabout 1,500 to about 3,000, in one embodiment about 1,800 to about2,300, in one embodiment about 700 to about 1300, in one embodimentabout 800 to about 1000, said first polyisobutene-substituted succinicanhydride being characterized by about 1.3 to about 2.5, and in oneembodiment about 1.7 to about 2.-1-In one embodiment, thehydrocarbyl-substituted carboxylic acid-acylating agent is apolyisobutene-substituted succinic anhydride, the polyisobutenesubstituent having a number average molecular weight of about 1,500 toabout 3,000, and in one embodiment about 1,800 to about 2,300, saidfirst polyisobutene-substituted succinic anhydride being characterizedby about 1.3 to about 2.5, and in one embodiment about 1.7 to about 2.1,in one embodiment about 1.0 to about 1.3, and in one embodiment about1.0 to about 1.2 succinic groups per equivalent weight of thepolyisobutene substituent.

The fuel-soluble product (i) may be formed using ammonia, an amineand/or the metal bases of metals such as Na, K, Ca, and the like. Theamines useful for reacting with the acylating agent to form the product(i) including but are not limited to, monoamines, polyamines, alkanolamines, hydroxy amines, and mixtures thereof, and amines may be primary,secondary or tertiary amines.

Examples of primary and secondary monoamines include ethylamine,diethylamine, n-butylamine, di-n-butylamine, allylamine, isobutylamine,cocoamine, stearylamine, laurylamine, methyllaurylamine, oleylamine,N-methyloctylamine, dodecylamine, and octadecylamine. Suitable examplesof tertiary monoamines include trimethylamine, triethylamine,tripropylamine, tributylamine, monoethyldimethylamine,dimethylpropylamine, dimethylbutyl-amine, dimethylpentylamine,dimethylhexylamine, dimethylheptylamine, and dimethyloctylamine.

The amines include but are not limited to hydroxyamines, such as mono-,di-, and triethanolamine, dimethylethanol amine, diethylethanol amine,di-(3-hydroxy propyl) amine, N-(3-hydroxybutyl) amine, N-(4-hydroxybutyl) amine, and N,N-di-(2-hydroxypropyl) amine; alkylene polyaminessuch as methylene polyamines, ethylene polyamines, butylene polyamines,propylene polyamines, pentylene polyamines, and the like. Specificexamples of such polyamines include ethylene diamine, diethylenetriamine, triethylene tetramine, propylene diamine, trimethylenediamine, tripropylene tetramine, tetraethylene pentamine, hexaethyleneheptamine, pentaethylene hexamine, or a mixture of two or more thereof;ethylene polyamine bottoms or a heavy polyamine. The fuel-solubleproduct (i) may be a salt, an ester, an ester/salt, an amide, an amide,or a combination of two or more thereof.

The fuel-soluble product (i) may be present in the water fuel emulsionat a concentration of up to about 15% by weight based on the overallweight of the emulsion, and in one embodiment about 0.1 to about 15% byweight, and an one embodiment about 0.1 to about 10% by weight, and inone embodiment about 0.1 to about 5% by weight, and in one embodimentabout 0.1 to about 2% by weight, and in one embodiment about 0.1 toabout 1% by weight, and in one embodiment about 0.1 to about 0.7% byweight.

The second acylating agent (ii) of this invention includes carboxylicacids and their reactive equivalents such as acid halides andanhydrides.

In one embodiment, the carboxylic acid is a monocarboxylic acid of about1 to about 35 carbon atoms, and in one embodiment about 16 to about 24carbon atoms. Examples of these monocarboxylic acids include lauricacid, oleic acid, isostearic acid, palmitic acid, stearic acid, linoleicacid, arachidic acid, gadoleic acid, behenic acid, erucic acid, tall oilfatty acids, lignoceric acid and the like. These acids may be saturated,unsaturated, or have other functional groups, such as hydroxy groups, asin 12-hydroxy stearic acid, from the hydrocarbyl backbone.

In one embodiment, the carboxylic acid is a hydrocarbyl-substitutedsuccinic acid represented correspondingly by the formula

wherein formula R is hydrocarbyl group of about 12 to about 35, and inone embodiment from about 12 to about 30, and in one embodiment fromabout 16 to about 24 and in one embodiment from about 26 to about 35carbon atoms. The production of such hydrocarbyl-substituted succinicacids or anhydrides via alkylation of maleic acid or anhydride or itsderivatives with a halohydrocarbon or via reaction of maleic acid oranhydride with an olefin polymer having a terminal double bond is knownto those of skill in the art.

In one embodiment, the acylating agent (ii) is a carboxylic acid or theacylating agent (ii) used to prepare carboxylic acid and is made byreacting one or more alpha-beta olefinically unsaturated carboxylic acidreagents containing about 2 to about 20 carbon atoms, exclusive of thecarboxyl based groups, with one or more olefin polymers containing atleast about 16 carbon atoms.

In the one embodiment, the ratio of the first acylating agent (i), tothe second acylating agent (ii) in the emulsified fuel is in the rangeof about 9:1 to about 1:9; in another embodiment in the range of about5:1 to about 1:5; and in another embodiment in the range of about 1:3 toabout 3.1.

The ionic or nonionic compound (iii) of the emulsifier has ahydrophilic-lipophilic balance (HLB, which refers to the size andstrength of the polar (hydrophilic) and non-polar (lipophilic) groups onthe surfactant molecule) in the range of about 1 to about 40, and in oneembodiment about 4 to about 15 and is described in greater detail inU.S. Ser. No. 09/761,482, An Emulsifier For An Aqueous Hydrocarbon Fuel,incorporated by reference herein. Examples of these compounds aredisclosed in McCutcheon's Emulsifiers and Detergents, 1998, NorthAmerican & International Edition. Pages 1-235 of the North AmericanEdition and pages 1-199 of the International Edition are incorporatedherein by reference for their disclosure of such ionic and nonioniccompounds having an HLB in the range of about 1 to about 40, in oneembodiment about 1 to about 30, in one embodiment about 1 to 20, and inanother embodiment about 1 to about 10. Examples include low molecularweight variants of (i) or (vii) such as those having a hydrocarbon groupin the range of C₈ or C₂₀. Useful compounds include alkanolamines,carboxylates including amine salts, metallic salts and the like,alkylarylsulfonates, amine oxides, poly(oxyalkylene) compounds,including block copolymers comprising alkylene oxide repeat units,carboxylated alcohol ethoxylates, ethoxylated alcohols, ethoxylatedalkylphenols, ethoxylated amines and amides, ethoxylated fatty acids,ethoxylated fatty esters and oils, fatty esters, fatty acid amides,including but not limited to amides from tall oil fatty acids andpolyamides, glycerol esters, glycol esters, sorbitan esters, imidazolinederivatives, lecithin and derivatives, lignin and derivatives,monoglycerides and derivatives, olefin sulfonates, phosphate esters andderivatives, propoxylated and ethoxylated fatty acids or alcohols oralkylphenols, sorbitan derivatives, sucrose esters and derivatives,sulfates or alcohols or ethoxylated alcohols or fatty esters, sulfonatesof dodecyl and tridecyl benzenes or condensed naphthalenes or petroleum,sulfosuccinates and derivatives, and tridecyl and dodecyl benzenesulfonic acids.

The emulsifier (iv) may be a mixture of (i) and (ii) described above andis further described in detail in U.S. Ser. No. 09/761,482, AnEmulsifier For An Aqueous Hydrocarbon Fuel, incorporated by referenceherein.

The emulsifier of the water-soluble compound (v) may be an amine salt,ammonium salt, azide compound, nitro compound, nitrate salts, alkalimetal salt, alkaline earth metal salt, or mixtures of two or morethereof and is described in greater detail in U.S. Ser. No. 09/761,482,An Emulsifier For An Aqueous Hydrocarbon Fuel, incorporated by referenceherein. These compounds are distinct from the fuel-soluble product (i)and the ionic or nonionic compound (ii) discussed above. Thesewater-soluble compounds include organic amine nitrates, nitrate esters,azides, nitramines and nitro compounds. Also included are alkali andalkaline earth metal carbonates, sulfates, sulfides, sulfonates, and thelike. In another embodiment the water soluble compound is in the form ofa salt, such as an amine salt, ammonia salt, azide salt, alkali metalsalt, alkaline earth metal salt, nitrate salt and mixtures thereof.

Particularly useful are the amine or ammonium salts such as ammoniumnitrate, ammonium acetate, methylammonium nitrate, methylammoniumacetate, hydroxy ammonium nitrate, ethylene diamine diacetate; ureanitrate; urea; guanidinium nitrate; and combinations thereof. However,these ammonium salts of the emulsifier, if used are independent of anddistinct and separate from the aqueous organic ammonium salt compound ofthe emulsified fuel discussed above.

In one embodiment the emulsifier (vi) is the reaction product of A) apolyacidic polymer, B) at least one fuel soluble product made byreacting at least one hydrocarbyl-substituted carboxylic acid acylatingagent, and C) a hydroxy amine and/or a polyamine and is described ingreater detail in U.S. Ser. No. 09/761,482, An Emulsifier For An AqueousHydrocarbon Fuel, incorporated by reference herein.

The polyacidic polymers used in the reaction include but are not limitedto C₄ to C₃₀; preferably C₈ to C₂₀ olefin/maleic anhydride copolymers;maleic anhydride/styrene copolymers; poly-maleic anhydride; acrylic andmethacrylic acid containing polymers; poly-(alkyl)acrylates; reactionproducts of maleic anhydride with polymers with multiple double bonds;

A copolymer of an olefin and a monomer having the structure:

wherein X and X1 are the same or different provided that at least one ofX and X₁ is such that the copolymer can function as a carboxylicacylating agent; and combinations therein.

The emulsifier produced from the reaction product of the polyacidicpolymer with the fuel soluble product (i) comprises about 25% to about95% of fuel soluble product and about 0.1% to about 50% of thepolyacidic polymer; preferably about 50% to about 92% fuel solubleproduct and about 1% to about 20% of the polyacidic polymer, and mostpreferably about 70% to about 90% of fuel soluble product and about 5%to about 10% of the polyacidic polymer. In one embodiment the emulsifieris described as a polyalkenyl succinimide crosslinked with anolefin/maleic anhydride copolymer.

The amino alkyl emulsifier (vii) is comprised of the reaction product ofan amino alkylphenol, an aldehyde, and an amine resulting in aminoalkylphenol. The amino alkylphenol can be made by (a) the reaction ofalkylphenol directly with an aldehyde and an amine resulting in analkylphenol monomer connected by a methylene group to an amine, (b) thereaction of an alkylphenol with an aldehyde resulting in an oligomerwherein the alkylphenols are bridged with methylene groups, the oligomeris then reacted with more aldehyde and an amine to give a Mannichproduct, or (c) a mixture of (a) and (b) and is described in greaterdetail in U.S. Ser. No. 09/977,747 entitled A Continuous Process ForMaking An Aqueous Hydrocarbon Fuel Emulsion incorporated by referenceherein.

The alkylphenols have an alkyl group selected from C₁ to C₂₀₀,preferably C₆ to C₁₇₀ wherein the alkyl group is either linear, branchedor a combination thereof. The alkylphenols include, but are not limitedto, polypropylphenol, polybutylphenol, poly(isobutenyl)phenol,polyamylphenol, tetrapropylphenol, similarly substituted phenols and thelike. The preferred alkylphenols are tetrapropenylphenol andpoly(isobutenyl)phenol.

The aldehydes include, but are not limited to, aliphatic aldehydes, suchas formaldehyde; acetaldehyde; aldol (β-hydroxy butyraldehyde); aromaticaldehydes, such as benzaldehyde; heterocyclic aldehydes, such asfurfural, and the like. The aldehyde may contain a substituent groupsuch as hydroxyl, halogen, nitro and the like; in which the substituentdoes not take a major part in the reaction. The preferred aldehyde isformaldehyde.

The amines are those which contain an amino group characterized by thepresence of at least one active hydrogen atom. The amines may be primaryamino groups, secondary amino groups, or combinations of primary andsecondary amino groups.

The amines include, but are not limited to, alkanolamines; di- andpolyamine (polyalkyene amines); polyalkyl polyamines; propylenediamine,the aromatic amines such as o-, m- and p-phenylene diamine, diaminonaphthalenes; the acid-substituted polyalkylpolyamines, and thecorresponding formyl-, propionyl-, butyryl-, and the like N-substitutedcompounds; and the corresponding cyclized compounds formed therefrom,such as the N-alkyl amines of imidazolidine and pyrimidine. Substituentgroups attached to the carbon atoms of these amines are typified byalkyl, aryl, alkaryl, aralkyl, cycloalkyl, and amino compounds. Theamino alkylphenols emulsifier of this invention may be made by reactingthe alkylphenol:aldehyde:amine in a ratio range of 1:1:0.1 molar to1:2:2 molar, in one embodiment preferably 1:0.9:0.1 to 1:1.9:1.9, in oneembodiment preferably 1:1.5:1.2 molar to 1:1.9:1.8 molar, and in oneembodiment preferably 1:0.8:0.3 to 1:1.5:0.7, resulting in the aminoalkylphenol emulsifier. In another embodiment of this invention theamino alkylphenol is made by the reaction of an alkylphenol with analdehyde, resulting in an oligomer wherein the alkylphenols are bridgedwith methylene groups; then the oligomer is reacted with more aldehydeand amine to give the emulsifier Mannich product of this invention. Thereaction is prepared by any known method such as an emulsion, asolution, a suspension, and a continuous addition bulk process. Thereaction is carried out under conditions that provide for the formationof the desired product.

The nitrogen-free emulsifier (viii) comprises:

(viii)(a) a hydrocarbyl substituted carboxylic acid, or a reactionproduct of the hydrocarbyl substituted carboxylic acid or a reactiveequivalent of such acid with an alcohol, the hydrocarbyl substituent ofthe acid or reactive equivalent thereof containing at least about 30carbon atoms; and

(viii)(b) at least one compound represented by one or more of theformulae:

wherein each R is independently hydrogen or a hydrocarbyl group of up toabout 60 carbon atoms; each R′ and R″ is independently an alkylene groupof 1 to about 20 carbon atoms; each R′″ is independently hydrogen, or anacyl or hydrocarbyl group of up to about 30 carbon atoms; n is a numberin the range of zero to about 50; and x, y and z are independentlynumbers in the range of zero to about 50 with the total for x, y and zbeing at least 1. This emulsifier is further disclosed in ApplicantsU.S. application entitled “Water Blended Fuel Composition”, Applicants'reference number 3134, U.S. Ser. No. 11/333,668, incorporated byreference herein.

The emulsifier component (viii) (a) may be a hydrocarbyl substitutedcarboxylic acid, or a reaction product of the hydrocarbyl substitutedcarboxylic acid or a reactive equivalent thereof with an alcohol. Thecarboxylic acids may be monobasic or polybasic. The polybasic acidsinclude dicarboxylic acids, although tricarboxylic and tetracarboxylicacids may be used. The reactive equivalents may be acid halides, (e.g.,chlorides), anhydrides or esters, including partial esters, and thelike.

The alcohol which may be reacted with the hydrocarbyl substitutedcarboxylic acid or reactive equivalent to form emulsifier component(iii)(a) may be a mono- or a polyhydric hydrocarbon-based alcohol suchas methanol, ethanol, the propanols, butanols, pentanols, hexanols,heptanols, octanols, decanols, and the like. Also included are fattyalcohols and mixtures thereof, including saturated alcohols such aslauryl, myristyl, cetyl, stearyl and behenyl alcohols, and unsaturatedalcohols such as palmitoleyl, oleyl and eicosenyl. Higher syntheticmonohydric alcohols of the type formed by the Oxo process (e.g.,2-ethylhexanol), by the aldol condensation, or byorganoaluminum-catalyzed oligomerixation of alpha-olefins (e.g.,ethylene), followed by oxidation, may be used. Alicyclic analogs of theabove-described alcohols may be used; examples include cyclopentanol,cyclohexanol, cyclododecanol, and the like.

The polyhydroxy compounds that may be used include ethylene, propylene,butylene, pentylene, hexylene and heptylene glycols; tri-, tetra-,penta-, hexa- and heptamethylene glycols and hydrocarbon-substitutedanalogs thereof (e.g., 2-ethyl-1,3-trimethylene glycol, neopentylglycol, etc.), as well as polyoxyalkylene compounds such as diethyleneand higher polyethylene glycols, tripropylene glycol, dibutylene glycol,dipentylene glycol, dihexylene glycol and diheptylene glycol, and theirmonoethers. A glycol that may be used is 1,2-propane diol.

Phenol, naphthols, substituted phenols (e.g., the cresols), anddihydroxyaromatic compounds (e.g., resorcinol, hydroquinone), as well asa benzyl alcohol and similar di-hydroxy compounds wherein the secondhydroxy group is directly bonded to an aromatic carbon (e.g., 3-HOφCH₂OHwherein φ is a divalent benzene ring) may be used. Sugar alcohols of thegeneral formula HOCH₂ (CHOH)₁₋₅ CH₂OH such as glycerol, sorbitol,mannitol, and the like, and their partially esterified derivatives maybe used. Oligomers of such sugar alcohols, including diglycerol,triglycerol, hexaglycerol, and the like, and their partially esterfiedderivatives may be used. Methylol polyols such as pentaerythritol andits oligomers (di- and tripentaerythritol, etc.), trimethylolethane,trimethylolpropane, and the like may be used.

The emulsifier component (viii)(a) may be in the form of an acid, anester, or a mixture thereof. The acid may be formed by reacting ahydrocarbyl substituted carboxylic acid reactive equivalent with waterto provide the desired acid. For example, hydrocarbyl (e.g.,polyisobutene) substituted succinic anhydride may be reacted with waterto form hydrocarbyl substituted succinic acid. The reaction between thehydrocarbyl substituted carboxylic acid or reactive equivalent thereofand the alcohol to form an ester may be carried out under suitable esterforming reaction conditions. In one embodiment, the hydrocarbylsubstituted carboxylic acid or reactive equivalent thereof and thealcohol are reacted in amounts sufficient to provide from about 0.3 toabout 3 equivalents of the acid or reactive equivalent thereof perequivalent of alcohol. In one embodiment, this ratio is from about 0.5:1to about 2:1.

The emulsifier component (viii)(b) may be at least one compoundrepresented by one or more of the formulae:

wherein each R is independently hydrogen or a hydrocarbyl group of up toabout 60 carbon atoms; each R′ and R″ is independently an alkylene groupof 1 to about 20 carbon atoms; each R′″ is independently hydrogen, or anacyl or hydrocarbyl group of up to about 30 carbon atoms; n is a numberin the range of zero to about 50; and x, y and z are independentlynumbers in the range of zero to about 50 with the total for x, y and zbeing at least 1. In the above formulae, R may be a hydrocarbyl group ofabout 6 to about 60 carbon atoms, and in one embodiment abut 6 to about45 carbon atoms, and in one embodiment about 6 to about 30 carbon atoms,and in one embodiment about 14 to about 30 carbon atoms. In oneembodiment, R may be a hydrocarbyl group of about 9 to about 11 carbonatoms. R′ and R″ may be independently alkylene groups of about 1 toabout 6 carbon atoms, and in one embodiment about 1 to about 4 carbonatoms. In one embodiment, R′ is an alkylene group containing about 2 toabout 3 carbon atoms, and in one embodiment about 2 carbon atoms. In oneembodiment, R″ is an alkylene group containing 1 carbon atom. R′″ may bean acyl or hydrocarbyl group of 1 to about 30 carbon atoms, and in oneembodiment 1 to about 24 carbon atoms, and in one embodiment 1 to about18 carbon atoms, and in one embodiment 1 to about 12 carbon atoms, andin one embodiment 1 to about 6 carbon atoms. n may be a number in therange of 1 to about 50, and in one embodiment 1 to about 30, and in oneembodiment 1 to about 20, and in one embodiment 1 to about 12, and inone embodiment about 4 to about 10, and in one embodiment about 5 toabout 10, and in one embodiment about 5 to about 8, and in oneembodiment about 5 or about 6. x, y and z may be independently numbersin the range of zero to about 50, and in one embodiment zero to about30, and in one embodiment zero to about 10; with the total of x, y and zbeing at least 1, and in one embodiment in the range of 1 to about 50,and in one embodiment 10 to about 40, and in one embodiment 20 to about30, and in one embodiment about 25.

Examples of compounds represented by formula (viii-b-1) that may be usedinclude: C₉-C₁₁ alkoxy poly (ethoxy)₈ alcohol; C₁₂-C₁₅ alkoxy poly(isopropoxy)₂₂₋₂₆ alcohol; oleyl alcohol pentaethoxylate; and the like.

Examples of compounds represented by formula (viii-b-2) that may be usedinclude diglycerol monooleate, diglycerol monosteaate, polyglycerolmonooleate, and the like.

Examples of compounds represented by formula (viii-b-3) that may be usedinclude polyethylene glycol (Mn=200) distearate, polyethylene glycol (Mn=400) distearate, polyethylene glycol (M n=200) dioleate, polyethyleneglycol (Mn=400) soya bean oil ester, and the like.

Examples of compounds represented by formula (viii-b-4) that may be usedinclude glycerol monooleate, diglycerol dioleate, diglycerol distearate,polyglycerol dioleate, and the like.

Examples of compounds represented by formula (viii-b-5) that may be usedinclude sorbitan monooleate, sorbitan monoisostearate, sorbitansesquioleate, and sorbitan trioleate, and the like.

Examples of compounds represented by formula (viii-b-6) that may be usedinclude polyethoxy glycerol trioleate wherein the compound contains 25ethoxy groups.

In one embodiment, the emulsifier (viii)(b) is an alkoxy polyethoxyalcohol wherein the alkoxy group contains about 14 to about 30 carbonatoms and the polyethoxy group contains up to about 10 ethoxy groups,and in one embodiment about 5 to about 10 ethoxy groups, and in oneembodiment about 5 or 6 ethoxy groups.

In one embodiment, the emulsifier (viii)(b) is an alkoxy polyethoxyalcohol wherein the alkoxy group contains about 9 to about 11 carbonatoms and the polyethoxy group contains about 8 ethoxy groups.

An optional acid component that may be used in one embodiment with thenitrogen free emulsifier and in another embodiment with each of theemulsifiers alone or in combinations may be used in the inventive fuelcomposition comprises one or more acids having a pKa of up to about 6,and in one embodiment up to about 5, and in one embodiment up to about4, and in one embodiment from about 0 to about 4, and in one embodimentabout 1 to about 3.5, and in one embodiment about 1.5 to about 3. Thisacid component includes but is not limited too carboxylic acid, formicacid, acetylenedicarboxylic acid, benzenehexacarboxylic acid,benzenepentacarboxylic acid, benzenetetracarboxylic acid,benzenetricarboxylic acid, 2-butyn-1,4-dioic acid, 2-butynoic acid,citraconic acid, cyclopropane-1,1-dicarboxylic acid,2,6-dihydroxybenzoic acid, dihydroxymaleic acid, dihydroxymalic acid,dihydroxytatric acid, alpha, alpha-dimethyloxaloacetic acid,dipropylmalonic acid, ethylene oxide dicarboxylic acid, hydroxyasparticacid, maleic acid, 2-oxobutanoic acid, triethylsuccinic acid, citricacid, tartaric acid, glyoxylic acid, oxalic acid, lactic acid,oxomalonic acid (mesoxalic acid), and mixtures thereof.

When used, this acid component may function as an ionizing agent. Theconcentration of this acid component in the water blended fuelcomposition may range up to about 5 percent by weight, and in oneembodiment from about 0.001 to about 3 percent by weight, and in oneembodiment about 0.01 to about 1 percent by weight.

Other Additives

In one embodiment, the emulsified fuel contains a cetane improver. Thecetane improvers that are useful include but are not limited toperoxides, nitrates, nitrites, nitrocarbamates, and the like. Usefulcetane improvers include but are not limited to nitropropane,dinitropropane, tetranitromethane, 2-nitro-2-methyl-1-butanol,2-methyl-2-nitro-1-propanol, and the like. Also included are nitrateesters of substituted or unsubstituted aliphatic or cycloaliphaticalcohols which may be monohydric or polyhydric. These includesubstituted and unsubstituted alkyl or cycloalkyl nitrates having up toabout 10 carbon atoms, and in one embodiment about 2 to about 10 carbonatoms. The alkyl group may be either linear or branched, or a mixture oflinear or branched alkyl groups. Examples include methyl nitrate, ethylnitrate, n-propyl nitrate, isopropyl nitrate, allyl nitrate, n-butylnitrate, isobutyl nitrate, sec-butyl nitrate, isooctyl nitrate,tert-butyl nitrate, n-amyl nitrate, isoamyl nitrate, 2-amyl nitrate,3-amyl nitrate, tert-amyl nitrate, n-hexyl nitrate, n-heptyl nitrate,n-octyl nitrate, 2-ethylhexyl nitrate, sec-octyl nitrate, n-nonylnitrate, n-decyl nitrate, cyclopentyl nitrate, cyclohexyl nitrate,methylcyclohexyl nitrate, and isopropylcyclohexyl nitrate. Also usefulare the nitrate esters of alkoxy-substituted aliphatic alcohols such as2-ethoxyethyl nitrate, 2-(2-ethoxy-ethoxy)ethyl nitrate,1-methoxypropyl-2-nitrate, 4-ethoxybutyl nitrate, etc., as well as diolnitrates such as 1,6-hexamethylene dinitrate. A useful cetane improveris 2-ethylhexyl nitrate.

The concentration of the cetane improver in the emulsified fuel is atany concentration sufficient to provide the emulsion with the desiredcetane number. In one embodiment, the concentration of the cetaneimprover is at a level of up to about 10% by weight, and in oneembodiment about 0.05% to about 10% by weight, and in one embodimentabout 0.05% to about 5% by weight, and in one embodiment about 0.05% toabout 1% by weight of the emulsified fuel.

In addition to the foregoing materials, other fuel additives that knownto those skilled in the art may be used in the emulsified fuel. Theseinclude but are not limited to dyes, rust inhibitors such as alkylatedsuccinic acids and anhydrides, bacteriostatic agents, gum inhibitors,metal deactivators, upper cylinder lubricants and the like.

The total concentration of the additives, in the emulsified fuel is fromabout 0.05% to about 30% by weight, and in one embodiment about 0.1% toabout 20% by weight, and in one embodiment about 0.1% to about 15% byweight, and in one embodiment about 0.1% to about 10% by weight, and inone embodiment about 0.1% to about 5% by weight of the emulsified fuel.

The additives, including the foregoing emulsifiers, may be diluted witha substantially inert, normally liquid organic solvent such as naphtha,benzene, toluene, xylene or diesel fuel to form an additive concentratewhich is then mixed with the fuel and water to form the emulsified fuel.

The emulsified fuel may contain up to about 60% by weight organicsolvent, and in one embodiment about 0.01% to about 50% by weight, andin one embodiment about 0.01% to about 20% by weight, and in oneembodiment about 0.1% to about 5% by weight, and in one embodiment about0.1% to about 3% by weight of the emulsified fuel.

The emulsified fuel may additionally contain an-antifreeze,agent. Theantifreeze agent is typically an alcohol. Examples include but are notlimited to ethylene glycol, propylene glycol, methanol, ethanol,glycerol and mixtures of two or more thereof. The antifreeze agent istypically used at a concentration sufficient to prevent freezing of thewater used in the water fuel emulsion. The concentration is thereforedependent upon the temperature at which the fuel is stored or used. Inone embodiment, the concentration is at a level of up to about 20% byweight of the emulsified fuel, and in one embodiment about 0.1% to about20% by weight, and in one embodiment about 1% to about 10% by weight ofthe emulsified fuel.

Engines

The engines that may be operated in accordance with the inventioninclude all (internal combustion) engines including spark ignited(gasoline) and compression ignited (diesel) for both mobile includinglocomotive, marine, automotive, truck, heavy duty, aviation and thelike, and stationary power plants. The engines may be two-cycle orfour-cycle. The engines may employ conventional after treatment devices.Included are on- and off-highway engines, including new engines as wellas in-use engines.

An open-flame burning apparatus may be operated with the emulsifiedwater fuel blend of the invention. The open-flame burning apparatus maybe any open-flame burning apparatus equipped to burn a liquid fuel.These include domestic, commercial and industrial burners. Theindustrial burners include those requiring preheating for properhandling and atomization of the fuel. Also included are oil firedcombustion units, oil fired power plants, fired heaters and boilers, andboilers for use in ships including deep draft vessels. The fuel burningapparatus may be a boiler for commercial applications included areboilers for power plants, utility plants, and large stationary andmarine engines. The open-flame fuel burning apparatus may be anincinerator or a rotary kiln incinerator, liquid injection kiln,fluidized bed kiln, cement kiln, and the like. Also included are steeland aluminium forging furnaces. The open-flame burning apparatus may beequipped with a flue gas recirculation system.

From the above description and examples the invention those skilled inthe art may perceive improvements, changes and modifications in theinvention. Such improvement changes and modifications are intended to becovered by the appended claims.

1. An emulsified water in oil composition comprising: A) a fuel; B) awater; C) a high molecular weight emulsifier; D) a surfactant having amolecular weight of about less than or equal to about 950 g/mol whereinthe surfactant comprises: i) natural fats; ii) fatty acids and theiramine salts; or iii) combinations thereof; and E) optionally ammoniumnitrate.
 2. The composition of claim 2 wherein a fuel is in the range ofabout 50% to about 99% by weight of the composition; the water is in therange of about 1% to about 50% by weight of the composition; theemulsifier is in the range of about 1% to about 50% by weight of thecomposition; and the surfactant in the range of about 0.001% to about15% by weight of the composition.
 3. (canceled)
 4. The composition ofclaim 1 wherein the fuel is a diesel fuel.
 5. The composition of claim 1wherein the water in oil composition is an emulsified water blended fueland wherein the fuel is selected from the group consisting ofFischer-Tropsch fuels, petroleum distillate fuel, diesel, gasoline, fueloil, vegetable sources, shale, coal, a biodegradable fuel; biodiesel;residual fuel; bitumen; alcohol; ether; ethanol; and combinationsthereof.
 6. The composition of claim 1 wherein the surfactant has a lowmolecular weight in the range of about 900 g/mol to about 30 g/mol. 7.The composition of claim 1 wherein the surfactant has a low molecularweight in the range of about 400 g/mol to about 90 g/mol.
 8. Thecomposition of claim 1 wherein the surfactant is in the range of about0.01% to about 10% by weight of the water in oil composition.
 9. Thecomposition of claim 1 wherein the natural fat surfactant is selectedfrom the group consisting of triglycerides, hydrolyzed triglycerides,oxidized products of triglycerides, vegetable oils, refined vegetableoils, used vegetable oils and combinations thereof.
 10. The compositionof claim 1 wherein the surfactants are amides derived from fatty acids,amides derived from fatty alcohols, ethers alcohols, fatty alcohols,esters of fatty acids ethers of fatty acides, esters of fatty alcoholsand combinations thereof.
 11. (canceled)
 12. (canceled)
 13. Thecomposition of claim 1 wherein the surfactants are selected from thegroup consisting of lauric acid, myristic acid, coconut acid, coconutoil, oleic acid, tall oil fatty acid, linoleic acid, soybean oil,apricot kernel oil, wheat germ oil, monocarboxylic fatty acids,triglycerides, and combinations thereof.
 14. (canceled)
 15. (canceled)16. The composition of claim 1 wherein the fatty acids and their aminesalt surfactants are selected from the group consisting of diethylethanolamine salts of oleic acid, tall oil fatty acids, stearic acid,palmitic acid, lauric acid and combinations thereof.
 17. A process formaking a water in oil composition comprising shearing; A) a fuel in therange of about 50% to about 99% by weight of the composition; B) a waterat less than 1% by weight of the compositionin the range of about 1% to50% by weight of the composition; C) a high molecular weight emulsifierin the range of about 1% to about 50% by weight of the composition; D) alow molecular weight surfactants in the range of about 0.001% to about15% by weight of the composition wherein the surfactant comprisesnatural fat; fatty acids and their amine salts; and combinations thereofand wherein the shearing mixing occurs at a shear rate in the range ofless than or equal to 50,000 s⁻¹; and E) optionally ammonium nitrate.18. The process of claim 17 wherein the shear rate in the range of about20,000 s⁻¹ to about 1 s⁻¹.
 19. The process of claim 17 wherein the shearrate is in the range of about 1,000 s⁻¹ to about 1 s⁻¹.
 20. The processof claim 17 wherein the water in oil composition is an emulsified waterin fuel and wherein the fuel is selected from the group consisting ofpetroleum distillate fuel such as diesel, gasoline, fuel oil and amixture thereof, a fuel derived from vegetables, corn, alfalfa,rapeseed, soybeans, shale, coal and mixtures thereof, a biodegradablefuel, biodiesel, residual fuel, bitumen, alcohol, ether, ethanol andcombinations thereof.
 21. The composition of claim 1 wherein theemulsifier is selected from the group consisting of A) at least onefuel-soluble product made by reacting at least onehydrocarbyl-substituted carboxylic acid acylating agent with ammonia oran amine including but not limited to alkanol amine, hydroxy amine, andthe like, the hydrocarbyl substituent of said acylating agent havingabout 50 to about 500 carbon atoms; B) a second acylating agent havingat least one hydrocarbyl substituents of up to about 40 carbon atoms,and reacting that said acylating agent with ammonia or an amine; C) awater-soluble compound selected from the group consisting of aminesalts, ammonium salts, azide salt, nitrate ester salt, alkali metalsalts, alkaline earth metal salts or mixtures thereof in combinationwith A, B, D, E, F or G; D) the reaction product of polyacidic polymerwith at least one fuel soluble product made by reacting at least onehydrocarbyl-substituted carboxylic acid acylating agent with ammonia, anamine, a polyamine, an alkanol amine or hydroxy amines; G) thecombination of (A), (B), (C), (D) or combinations thereof.
 22. Thecomposition of claim 1 wherein the water in oil composition is anemulsified fuel used to operate an apparatus selected from the groupconsisting of an engine, an open flame burner, and an internalcombustion engine.
 23. A process for making a water in oil compositioncomprising shearing; A) a fuel in the range of about 50% to about 99% byweight of the composition; B) a water in the range of less than about 1%by weight of the composition; C) a high molecular weight emulsifier inthe range of about 1% to about 50% by weight of the composition; D) asurfactant having a molecular weight of about less than or equal toabout 950 g/mol in the range of about 0.001% to about 15% by weight ofthe composition wherein the surfactant comprises natural fat; fattyacids and their amine salts; and combinations thereof and wherein theshearing mixing occurs at a shear rate in the range of less than orequal to 50,000 s⁻¹; and E) optionally ammonium nitrate.
 24. The processof claim 23 wherein the water is in the range of about 0.01% to lessthan 1% by weight of the composition.
 25. A process for making a waterin oil composition comprising shearing; A) a fuel in the range of about50% to about 99% by weight of the composition; B) a water in the rangeof less than about 1% by weight of the composition; C) a high molecularweight emulsifier in the range of about 1% to about 50% by weight of thecomposition; and D) a surfactant having a molecular weight of about lessthan or equal to about 950 g/mol in the range of about 0.001% to about15% by weight of the composition wherein the surfactant comprisesnatural fat; fatty acids and their amine salts; and combinations thereofand wherein the shearing mixing occurs at a shear rate in the range ofless than or equal to 50,000 s⁻¹.
 26. (canceled)